KVM: arm64: nv: Make AT+PAN instructions aware of FEAT_PAN3

FEAT_PAN3 added a check for executable permissions to FEAT_PAN2.
Add the required SCTLR_ELx.EPAN and descriptor checks to handle
this correctly.

Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
index e037eb73738a355ebc05a173f0a2184987b626e5..60f1ca3a897d927328e850790b5370a49c10901f 100644 (file)
--- a/arch/arm64/kvm/at.c
+++ b/arch/arm64/kvm/at.c
@@ -731,6 +731,21 @@ static u64 compute_par_s1(struct kvm_vcpu *vcpu, struct s1_walk_result *wr,
        return par;
 }
 
+static bool pan3_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime)
+{
+       u64 sctlr;
+
+       if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR1_EL1, PAN, PAN3))
+               return false;
+
+       if (regime == TR_EL10)
+               sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
+       else
+               sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL2);
+
+       return sctlr & SCTLR_EL1_EPAN;
+}
+
 static u64 handle_at_slow(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
 {
        bool perm_fail, ur, uw, ux, pr, pw, px;
@@ -797,7 +812,7 @@ static u64 handle_at_slow(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
                        bool pan;
 
                        pan = *vcpu_cpsr(vcpu) & PSR_PAN_BIT;
-                       pan &= ur || uw;
+                       pan &= ur || uw || (pan3_enabled(vcpu, wi.regime) && ux);
                        pw &= !pan;
                        pr &= !pan;
                }